A fast flow reactor-quadrupole mass spectrometer system coupled with a laser vaporization source is used to study the gas-phase reactions of nickel and nickel oxide cluster cations with nitric oxide. Pseudo-first-order bimolecular rate constants are reported for the reactions of NO with nickel and nickel oxide duster cations and O-2 reactions with nickel cluster cations. The product distributions indicate chat several different reaction mechanisms occur between NO and Ni-x(+) and NixOy+. Competing processes such as oxidation, NO addition, and replacement of oxygen with nitric oxide are observed to occur. Also, the presence of magic peaks in the distributions indicates unusually stable product cluster species.